Although breast milk is undeniably the best nutrition for infants, <30% of the 4 million new mothers can keep up with the demands of pumping. This is particularly challenging for working mothers who must rely on using a breast pump, proven to be less efficient and effective than breastfeeding infants, for 20% of their work day to provide enough breast milk for their babies. Our long-term objective is to develop a novel compression-based breast pump that would allow new mothers to effectively, comfortably and conveniently express breast milk while they are away from their infants. This technology would assist women in meeting their breastfeeding goals, improve the health of their infants, and help remove the barriers to milk expression and collection in the workplace. The proposed project is focused on understanding and refining the optimal stimulation pattern for a compression-based breast pump for augmenting efficiency, efficacy and comfort as well as assessing the relative effectiveness compared to a standard commercially available vacuum breast pump. In specific aim 1, we will evaluate milk volumes of our existing prototype to different compressive stimulation patterns. In specific aim 2, we will evaluate the breath of compression technology opportunities by studying the effectiveness of standalone compression technology vs existing vacuum technology as well as the added benefit of using both technologies in combination. Together these studies will be instrumental in understanding of the comfort and efficacy, in terms of milk ejection reflex and total volume over time, of different compression stimulation patterns and in comparison to a commercially available vacuum breast pump. With this, we can leverage our results to generate impactful marketing materials to discuss with influential clinical decision makers, such as lactation consultants, midwifes, and obstetricians who routinely guide new mothers in their breast pump purchase. The information learned from the clinical testing can also be translated into lay-person language to help mothers understand general efficacy as well as how the technology relates to the safe and effective method of hand expression.